Fury van der Rhys, daughter of Sirena, the Sea Siren, who twenty years before had plundered the ships of the Dutch East India Company, sets sail for the coast of Africa to challenge Amalie, a gorgeous creature who shares Fury's love for a dark-eyed Spaniard.

Whip Darling, a recognized expert on the deep, ponders the cause of a bizarre series of events out in the sea. Under the water, something is moving, something incredible, and savage and huge.